Shipping container



9, 1949. R. A. NORBOM 2,478,777

SHIPPING CONTAINER Filed Oct. 27, 1947 4 SheecsSheet'l Cl I' E \f b/ Aug. 9, 1949. R. A. NORBOM SHIPPING CONTAINER 4 Sheets-Sheet 2 Filed Oct. 27, 1947 Wm w MM 4 & Y/IIIIII IIIIIII run; wnnuunnnIpunnnnnnlnnnnnlnnunu "an"Iuullnunvnnnnun 9, 1949- R. A. NORBOM 2,478,777

7 I SHIPPING CONTAINER Filed Oct. 27, 1947 4 Sheets-Sheet 3 Hayward jVorbo m Aug. 9, 1949. R. A. NORBOM SHIPPING CONTAINER Filed 001;. 27, 1947 4 Sheets-Sheet 4 Ragnar-14. )Vorbom Patented Aug. 9, 1949 SHIPPING CONTAINER Ragnar A. Norbom, New York, N. Y., assignor to National Fitch Corporation, a corporation of Delaware Application October 27, 1947, Serial 'No. 782,305

13 Claims. y l This invention relates to means for the transfer or discharge of finely divided bulk material such as grain, powdered chemicals, minerals, and more especially flour'or other granulated or pulverized food products that are capable of being entrained in an" air stream; More particularly this invention pertains to discharge means for'such material in association with a container, the latter being of the transportable type or a stationary storage bin. It is advantageous to transport and/or store finely divided food, particularly flour, in bulk form in rather large, substantially airtight containers instead of in the conventional packaged form of relatively small sacks, cartons, or barrels. Among the advantages of such largecontainers that may be enumerated are the elimination of packaging expense, the reduction of multiple handling charges, the elimination 'of losses through package breakage, and the overcoming of contamination hazards of moisture, vermin, and like nuisances. Thesuccessful employment of large containers for flour, however, depends in large measure upon the efiiciency of the un loading or discharging means therefor.

Pneumatic conveyor systems are widely used at present for transferring finely divided bulk material from point to point, and have been applied to the unloading of bulk material from large containers, such as, for example, railway cars. Suction discharge of' large containers,

however, has met with diflioulties. Finely divided bulk material, and-notably flour, has some fluid characteristics, yet is subject to packing on being transported or stored for considerable time and thereby loses much of its free-flowing characteristics. Accordingly, for suction discharge of such material, means usually are provided for either moving the material to the suction discharge nozzle or opening, 'or moving the nozzle relative to the material. Among the means employed for practicing the former method are spiral conveyors, interior slope sheets, or tilting of the container. Manual manipulation is the prevalent method of moving the suction nozzle to'the material. All of these means, however, have disadvantages. Spiral conveyors are expensive and require a source of substantial mechanical power. Slope sheets reduce the useful cubic content of a container.

A tiltable container is restricted in size for practical reasons. Manual manipulation of a suction nozzle is ineflicient and increases the contamination hazard.

to provide a large container for bulk material with simple and comparatively inexpensive pneumatic discharge means which is eiiicient in operation.

Another object of the invention isto provide such a container with discharge means which is operative without tilting the container and which does notrequire the use of interior slope sheets or a spiral conveyor. a

A further object of this, invention is to provide a container of the type described with improved. means for pneumatically effecting the complete discharge of the contents thereof ina minimum of time.

Other objects and advantages of the invention will be evident from thefollowing description andaccompanying drawings. The invention is illustrated by the application thereof to a railway car, but it will be obvious that a stationary storage bin, a highway vehicle body, a demountable container, or storage bins, in the holdof a ship may embody the invention as well.

In the drawings:

Figure, 1 is a side elevational view, partly in section, of a railway car embodying this invention. e

Figure. 2 is an end view of the railway car shownin Figure 1 having the pneumatic discharge system connected thereto.

Figure 3 is an enlarged fragmentary vertical sectional view corresponding to Figure l. t

Figure 4 is a sectional view taken on line 4--4 of Figure 3. a

Figure 5 is an enlarged fragmentary view of one end of the car shown in-Figure 1 with portions broken away to show details more clearly. Figure 6 is an enlarged fragmentary view of a portionof Figure 5. 1 Figure? ,is an enlarged fragmentary View of a portion of Figure 3.

Referring now to Figures 1 and 2, there is shown a railway car with an underframe generally indicated at I0, and having a tank type container ll mounted thereon. For transporting flour or other finely divided food products, the container preferably is constructed of wood, with'a metal outer covering [2, as shown. Any other construction, however, such'as a metal interiorwith or without insulation and covering, can be used for transporting materials which are not so subject to deterioration from temperature changes or condensation. The container is shown as cylindrical in transverse vertical section,=although it will be seen that it may be Accordingly, it is an object of this invention oval, square, or any other substantially symtainer H is a tubular conduit l6, which serves as a guide rail, as later described, each end of which is secured in a corresponding end wall I! of the container, and opens to the exterior thereof. Radial braces l8 (see Figures 1, 3 and 5) support the conduit l5 at the mid-point thereof, centrally of the container. In communication with the interior of each end of the eonduit l6 and depending therefrom to a point adjacent the suction discharge outlet I5 is an entraining air inlet duct I!) which flares transversely of the container, as shown in Figure 5, and narrows longitudinally of the container, as shown in Figure 3, toward its outlet end.' An air filter 2D is mounted in each end of the conduit IE to filter the air to be delivered to the ducts l9. The outer ends of the conduit |6 may be provided with removable closures, not shown in the drawings, to prevent entrance of air, etc. to the container interior, save during a discharge operation.

Mounted for longitudinal slidable movement on the conduit l6 are two identical bulkheads 2|, one on each side of the center braces l8. These bulkheads define two compartments 22 within the container, one between each bulkhead and a corresponding end wall ll. Since both halves of the container, on opposite sides of the center braces l8, are substantially identical, a description of one half of the container will sufiice for both.

The bulkhead 2| is imperforate save for the central circular opening through which the conduit I6 extends, in order that the bulkhead may act as a follower, as later described. The outer and inner peripheries of the bulkhead 2| sealingly engage the side walls of the container H and outer walls of the conduit |5,-respectively. The seal between the bulkhead and the container walls is effected by an annular composite gasket 23 replaceably mounted between outer radial flanges 24, one of which is detachable, as'shown.

The gasket 23 preferably comprises an inner cushion 25 of sponge or soft rubber and an outer packing 26 of hard rubber or material of similar characteristics which contacts the walls of the container. sion Wear, while the inner cushion 25 compensates for irregularities in the surface of the container wall and also for any axial deflection of the conduit Hi. The seal between the bulkhead and the conduit |6 comprises an annular gasket 21, of rubber or other suitable material, replaceably mounted in a seat 28 at one end of the inner periphery of the bulkhead. A detachable annular retaining member 29 holds the gasket 2'! in place.

The bulkhead is provided with two longitudinally spaced circumferential series of rollers 30 which bear against the conduit l5 and support the bulkhead 2| for longitudinal movement therealong. The provision of a circumferential series of rollers 36 (see Figure 4) permits the bulkhead 2| to turn or rotate on its axis,v in order to prevent binding which might result from screw action during its longitudinal movement. The longitudinal spacing of the rollers 30 prevents the The hard rubber packing 26 resists abra- 4 bulkhead 2| from tilting or canting relative to the conduit l6 because of uneven resistance to its movement caused by flour or other powdered material being packed and more dense at the bottom of the container than at the top.

That side of the bulkhead 2| which faces the center braces H3 is provided with a shoulder or flange 3|, with which a latch 32 may engage, as best shown in Figure 7, to lock the bulkhead in the center of the container against longitudinal movement. The latch 32 is mounted for pivotal movement on lugs 33, which depend from the conduit, and is operated by a transverse rod 34 having a central eccentric portion 35 which passes through a slot 36 in the latch. The rod 34 is rotatably mounted in lugs 31 secured to the braces I8 and sealingly extends through opposite side walls of the container II. An exterior operating handle 38 is provided on each end of the rod 34 for turning the same to raise and lower the latch 32. As shown in Figure 7, the latch when raised is in locking position.

Opposite longitudinal movement of both bulkheads 2|, either simultaneously or independently, is effected by compressed air admitted to the space therebetween through apertures, in the form of stub pipes 33, in opposite side walls of the container (see Figure 5). The outer end of each pipe 39 is adapted to have a compressed air hose 40 detachably connected thereto, as shown in Figure 2, and in the absence of such connection is sealed by a closure 4| which is springbiased to closed position. An annular member 42 is secured to the conduit I6, adjacent the end thereof, to engage and stop the travel of the bulkhead 2| before it reaches the end wall IT, for a purpose later described.

A transversely extending trough 43 depends from the container bottom, adjacent the end wall ll. The flared outlet of the air inlet duct l9 overhangs the trough 43 and extends parallel to the central portion of the bottom thereof. A suction discharge outlet 44 opens centrally through the bottom of the trough 43 into a transversely positioned suction discharge conduit 45, to either end of which a suction hose 46 may be detachably connected, as shown in Figure 2. Each end of the conduit is readily accessible through an opening 41, normally closed by a pivotally mounted closure 48, in the metal side sheathing |2 of the car. On each side of the discharge outlet 44, a valve or gate 49 is mounted in the conduit 45 on a shaft 50 which extends through a lateral wall of the conduit and is provided with an operating lever 5 I. The valves 49 may pivot into open position by gravity action combined with the suction force applied to a corresponding end of the conduit 45. The valves are closed through the reciprocating action of screws 52 threadedly engaged through lugs 53 which are mounted on the exterior of the conduit. One end of each screw 52 bears against a corresponding lever 5| while the other end is engaged for rotative movement by the suitably shaped end of an operating rod or shaft 54. The outer end of the rod 54 is supported by and extends through a bracket 55 which latter also supports the outer end of the conduit 45. Operating handles 56 are provided for rotating the rods, and these handles are accessible through the side wall openings 41. It readily will be seen that rotation of a screw 52 in one direction, by a handle 56, forces a valve to closed position, while rotation in the opposite direction permits the valve to open under gravity aided by stood. however, that the simple" expedient: of a suitable mechanical connectionbetween the-levers- 5i and the screws 52- readi-ly may be provided so that positive opening of the valves may be eifected by operation of the handles 58.

The discharge of the contents of the container may be elfected at any unloading point that is equipped with known facilities including a source of compressed air and additionally a pneumatic conveyor system. The equipment necessary for unloading the car is illustrated diagrammatically in Figure 2. This includes the flexible suction hose 46 of a; pneumatic conveyor system which leads to a separator for discharge into a storage bin, and a compressor 5'! and flexible hose 40. The compressor should have readily accessible output and intake connections 58-v and 59', respectively, for. a purpose later described.

The operation of the invention, as above described, is as follows. With. the bulkheads 2| locked. in the center of the container by the latches 32 and the valves 49 closed, either or both compartments 22 of. the container can be filled with finely dividedi materialthrough the filling openings It. When the container is filled, the sealing closures it are replaced. Such filling may be accomplished by any conventional means, i. e. by gravity from an overhead hopper or by a hose forminga part of a pneumatic conveyor system. The car-then is transported to its final destination and spotted beside an unloadingplatformsuch as that illustrated in Figure 2. The operatorjthen attaches the suction hose 46 to one endof the discharge conduit 45 and removes the closures for the ends of the conduit it. One handle 56 is then operated to, open the valve 49;, corresponding to that end of the discharge conduit. to which the suction hose is attached, and the suction of thehose turned on. Next; the compressed air hose 40 is attached between a stub pipe 39 and the output connection 58, of the compressor 5'1. Assuming the compressor to be in operation, it will force air into the space between the bulkheads.

When. only one compartment of the container i is being unloaded ata time, i. e. when only one suction hose is employed, one-handle 38 is turned to unlock and release the bulkhead correspondingto that compartment. The bulkhead will travel toward the corresponding endwall ll of the container, under the influence of air pressure, and acts as a follower to push the contents of the compartment before it and into the outlet trough 43. The bulkhead moves at a rate depending mainly on the rate of suction evacuation of the material through the discharge opening 44 and conduit $5. The air inlet system for the container, .via the conduit I6, is necessary to relieve vacuum within the container as the discharge progresses, and also to provide an air current adjacent opening 44 which serves to agitate and entrain the material. The wide flaring outlet of the duct l9 directs a current of air over that portion of the entire bottom of the trough 43 which is substantiall horiz ntal, and acts to sweep the material intothe discharge outlet 54. The remaining bottom surfaceof the trough, i. e. adjacent the ends thereof, has an inclination sufiicient for gravity movement of the material therealong.

When the bulkhead reaches the limit of its permissible travel, it engages the stop member 42, which is effective to prevent the gasket 23 from over-running the depression 43 or engaging and possibly damaging the duct l9. With all the material- .then evacuated from thezconipart-i ment, the suction is 'shut? off, the valve. 48 closed, and; the suction boss 46 disconnected. The com,- pressed air hose .40 is disconnected from theoutzputconnection 58 connected tothe compressor intake 59. The compressor will theni'draw a eacuum; between. the; bulkheads which returns the advanced-bulkhead back to its central position where it is locked in place to prevent movement during transit or while the other compartment isbeing unloaded in a: similar manner. 1, Obvious ly,',"w-ith. suitable terminal facilities, both m? partments of the container can be, discharged simultaneously. 7 The compressor preferably incorporatesa-suitable pressure switch (not shown) which acts to limit the pump to apredetermined pressure in order to prevent the bulkhead fr0m pressing againstthe lading with an excessive force. ,Because the bulkheads are comparativelylarge the air pressure normally required to efiect their movement is relatively low, a few poundsper squareinchbeing sufficient. 1 ,It .will be noted also that the container may be unloaded fronreither side for added convenienceinusaf f (It will be realized that the. specific structure shown and described readily is subject to changes which incorporate the primary principles or the invention. Therefore, the invention encompasses all modifications and embodiments which come within the spirit and scope of the following claims. I

II'claim: I" a I. A closed container for finely divided bulk material having uniform cross-section, a suction discharge outlet located in a lower wall portion at one 'end of said container, an inlet foriinatrialjentraining air overhanging said outlet in close proximity thereto, a piston-like follower mounted for longitudinally slidable movement within said container, and means to admit fluid under pres sure to said container on that side of said follower remote from said outlet, whereby admission of said pressure fluid forces said follower to move toward said outlet to mechanically impel the con :tents of said container toward said outlet forsuction discharge; 1 2. A closed'container for finely divided bulk material having uniform cross-section, a suction discharge outlet located in a lower wall portion at one end of said container, an inlet for materialentraining air overhanging said outlet in close proximity thereto, a longitudinal guide member mounted within said container, a piston-like follower mounted on said guide member for slidable movement therealong, said follower having sealing engagement with said guide member and with the side walls of said container, and means to admit fluid under pressure to said container between the other end thereof and said follower, whereby admission of said pressure fiuid forces said follower to move toward said outlet to me; 'chanically impel the contents of said container toward said outlet for suction discharge. V :3. The structure defined by claim 2, wherein the follower is mounted on the guide member by longitudinally spaced rollers.

'4. The structure defined by claim 2, wherein the container and the guide member are cylindrical and the follower is mounted on said guide member by at least one series of rollers circumferentially arranged with reference to said guide member.

5. The structure defined by claim 2, including latching means for locking the follower against movement at that end of the travel thereof remote from the discharge outlet and a handle accessible exteriorly of the container for operating said latching means.

6. A closed container for finely divided bulk material, a suction discharge outlet located in a lower wall portion at one end of said container, a longitudinal conduit secured to, and opening to the exterior of at least one of, the end walls of said container, a follower mounted on said conduit for slidable movement therealong, said follower having sealing engagement with said conduit and with the side walls of said container, an air inlet duct for material-entraining air in communication with and depending from said conduit adjacent said one end of the container, said duct having an outlet adjacent said suction discharge outlet, and means to admit fluid under pressure to said container on that side of said follower remote from said suction discharge outlet.

7. A closed container for the transportation of finely divided bulk material, a piston-like follower mounted for longitudinally slidable movement therein, a transverse discharge trough depending from a lower wall portion at one end of said container, a suction discharge outlet opening through the bottom of said trough, an air inlet duct for material-entraining air in communication with the exterior of said container, said duct having a narrow flaring outlet aligned with and overhanging said trough, and means for admitting fluid under pressure to said container on that side of said follower remote from said trough, whereby admission of said pressure fluid forces said follower to move toward said trough to mechanically impel the contents of said container into said trough for suction discharge therefrom.

8. A closed container for finely divided bulk material, a piston-like follower mounted for longitudinally slidable movement therein, a suction discharge outlet located in a lower wall portion at one end of said container, an inlet for materialentraining air adjacent said outlet, a transversely disposed suction discharge conduit having communication intermediate the end thereof with said suction discharge outlet, each end of said conduit being adapted for connection with a suction hose of a pneumatic conveyor system, and

valve means in said conduit to control the discharge of material therethrough, one on each side of the point of communication of said conduit with said suction discharge outlet.

9. A closed container for the transportation of finely divided bulk material, a longitudinal conduit secured to, and opening to the exterior of at least one of, the end walls of said container, a follower mounted on said conduit for slidable movement therealong, said follower having sealing engagement with said conduit and with the side walls of said container, a transverse discharge trough depending from a lower wall portion at one end of said container, a suction discharge outlet opening through the bottom of said trough, an air inlet duct for material-entraining air in communication with and dependin from said conduit adjacent said one end of the container, said duct having a narrow flarin outlet aligned with and overhanging said trough, and means to admit fluid under pressure to said container on that side of said follower remote from said trough.

10. A closed container for the transportation of finely divided bulk material having uniform cross-section, a discharge outlet located in a lower wall portion at each end of said container, a longitudinal guide member mounted within said container and extending from end wall to end wall thereof, a pair of piston-like followers mounted on said guide member for slidable movement therealong, said followers having sealing engagement with said guide member and with the side walls of said container, and means to admit fluid under pressure to said container between said followers.

11. The structure defined in claim 10 including latching means for selectively locking said followers against movement at substantially midway of the length of said container.

12. A closed container for finely divided bulk material having uniform cross-section, a discharge outlet located in a lower wall portion at each end of said container, a longitudinal conduit mounted within said container, secured to, and opening to the exterior of at least one of, the end walls thereof, an air inlet duct for materialentraining air in communication with and depending from each end of said conduit, each of said ducts having an outlet adjacent the corresponding suction discharge outlet, a pair of followers mounted on said conduit for slidable movement therealong, said followers having sealing engagement with said conduit and with the side walls of said container, and means to admit fluid under pressure to said container at substantially midway of the length thereof between said followers.

13. A closed container for finely divided bulk material, a pair of piston-like followers mounted for longitudinally slidable movement therein, a transverse discharge trough depending from a lower wall portion at each end of said container, a suction discharge outlet opening through the bottom of each trough, an air inlet duct in communication with the exterior of said container adjacent each end thereof, each of said ducts having an outlet adjacent the corresponding trough, and means to admit fluid under pressure to said container substantially midway of the length thereof between said followers, whereby admission of said pressure fluid forces said followers to move in opposite directions toward said troughs to mechanically impel the contents of said container into said troughs for suction discharge.

RAGNAR A. NORBOM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,038,781 Myles Sept. 17, 1912 1,116,639 Spencer Nov. 10, 1914 1,362,767 Webb Dec. 21, 1920 

